Human papillomavirus (HPV) is the most common sexually transmitted infection in the United States, and nearly half of all American women in their early 20s are infected. This is a concern because HPV is the causative agent for nearly all cervical cancer, the second most common cancer in women worldwide. With the 2006 licensure of human papillomavirus (HPV) vaccine, vaccination innovation entered a new era in which inoculation has the potential to confer a high level of protection against cervical cancer. Nevertheless, nearly one in four parents refused the HPV vaccine for their adolescent daughters. Vaccine refusal is an unfortunately common occurrence despite the fact that most parents claim that medical professionals are a trusted source of vaccine information. Social norms (defined as the proscriptive and descriptive group characteristics that are one means by which people are influenced by others) likely have a strong influence on parental vaccine decisions especially among populations with greater mistrust of the medical establishment. African-Americans have lower HPV immunization coverage than whites and higher cervical cancer incidence and death rates. African-American parents have also expressed a greater mistrust in professional medical advice than other racial groups. Studies have demonstrated that peer norms related to certain health behaviors are influenced by personal networks of friends, colleagues and associates. In fact, African- Americans claim to trust the recommendations of their family, church or core community more than their physician's advice. Attributes of social network function (i.e., the type of interaction provided by the network- such as health advice or emotional support), network structure (e.g., its size or density) and network demographic composition (e.g., gender and age of associates) have been found to be associated with normative values related to health. Nevertheless, there has not been an examination of the association of social network and norms related to childhood vaccines and parental vaccine refusal. Furthermore, there has not been a study of which particular social norms are associated with vaccine refusal. The goal of the proposed investigation is to examine the social network factors associated with negative vaccine norms and decision-making relevant to HPV vaccination among African-American parents. We will achieve this goal through a cross-sectional study of African American parents of girls in the indicated age range for routine HPV vaccination (11-12 years). Based on the formative work's findings, we will develop and obtain feedback on an intervention in which vaccine opinion-leaders send to their peers voice or text messages countering negative vaccine norms in their own words. Ultimately, this study is intended to inform the design of a peer vaccination outreach intervention that could be piloted in subsequent investigations to reduce HPV vaccine refusal among African-American parents and potentially reduce the incidence of cervical cancer. PUBLIC HEALTH RELEVANCE: Parental refusal of childhood vaccines on behalf of their children is an increasingly common public health problem which has lead to disease outbreaks. African Americans have lower childhood vaccination rates and greater mistrust of the medical establishment than other racial/ethnic groups. Understanding how personal support networks and normative values among African-American parents are associated with vaccine decision- making may help us develop more effective peer outreach interventions to increase vaccine acceptance among African-American parents and reduce the incidence of vaccine-preventable diseases.